XPRIZE chief names organ biostasis prize as winner of competition for prize ideas, with a six-month storage target and testing in pigs

XPRIZE chief names organ biostasis prize as winner of competition for prize ideas, with a six-month storage target and testing in pigs

XPRIZE awards prizes for solving major challenges. At its Global Visioneering summit on October 15–17, participants were to assess ideas for future competitions, vote and pledge initial funding. In the October 17 episode of the Moonshots podcast, XPRIZE CEO Anousheh Ansari named the organ biostasis prize as the winner. Biostasis means stopping or slowing metabolism.

A kidney removed for transplantation can be stored for 24–36 hours, leaving that much time to get it to the recipient. According to the US transplant network OPTN, 95 492 people were waiting for a donor kidney as of July 30, 2026. Speaking about the summit, Ansari said: “There were organ transplant recipients in the room, and they all described how difficult it is, for yourself or someone you love, to wait and see whether a suitable organ will become available in time to save a life.”

XPRIZE founder and podcast host Peter Diamandis described the idea: “If organs can be placed in biostasis, whether cryogenic or metabolic, they can sit on a shelf until a suitable recipient is found.” Ansari set a target of six months of storage and estimated the current maximum at two weeks; another speaker countered that current storage times are measured in hours and vary by organ. According to Diamandis, the test would involve removing an organ from a pig, keeping it in biostasis for months and transplanting it back into the same animal, which must survive.

Ice is a hazard during freezing because water crystals damage cells. A pig kidney is similar in size to a human kidney and weighs about 100 grams, while a rat kidney weighs about a gram. In a kidney the size of a pig’s, the centre cools more slowly, and the cryoprotectant, a substance that protects cells during freezing, penetrates the tissue unevenly. The previous cryoprotectant formulation, which preserved rat kidneys for up to 100 days, prevented ice formation only at cooling rates faster than those achievable at the centre of a pig kidney, so the researchers had to develop a new formulation.

Matthew Powell-Palm’s group at Texas A&M University stored kidneys for up to 72 hours at −4 °C in a chamber where pressure prevents water from freezing. Each kidney was transplanted back into the pig it came from, and the other kidney was removed, leaving the transplanted kidney solely responsible for filtering the blood. One of these pigs was monitored for 200 days. At Massachusetts General Hospital in 2025, researchers transplanted a kidney into a pig after 10 days of storage at −15 °C in a partially frozen state: ice formed around the cells, while a cryoprotectant protected the cells themselves. The kidney began producing urine during surgery. In a preprint, a University of Minnesota group reported storing kidneys at −150 °C in an ice-free, glass-like state and warming them from within using nanoparticles. One kidney was stored for 366 days and produced urine on a machine that circulated blood through it; kidneys transplanted into pigs were monitored for two hours.

A related proposal, Organ Preservation XPRIZE, reached Visioneering. It was submitted by scientists from ATP-Bio, a centre for the preservation of biological systems. In September, the team reported that its proposal had received the highest score at the XPRIZE expert conclave. The team includes a researcher behind each of the three approaches: John Bischof of the University of Minnesota, Matthew Powell-Palm and one of the developers of the partial freezing method at Massachusetts General Hospital.

The prize requirement brings together in one experiment outcomes demonstrated separately with pig kidneys: a pig surviving for 200 days with a kidney stored for up to 72 hours, transplantation after 10 days of freezing, and 366 days of storage for a single kidney. The Minnesota group identifies pig experiments with longer follow-up as its next step; the prize adds months of storage to those experiments.